The present invention relates to ceiling grid systems, which are typically constructed using "T" grid beams, joined to form a supporting grid system upon which drywall or lay-in panels can be mounted. A typical "T" grid beam is an elongated beam with a flange at the bottom of the beam and a thicker "bulb" portion at the top end of the beam. Thus, the cross section of the beam resembles an inverted "T" shaped configuration. The bottom of the flange provides the grid face for the attachment of drywall, ceiling tiles, acoustical panels or other types of panels. Typically, these grid beams are made of extruded aluminum or roll-formed steel, and can be straight or curved.
Ceiling grid systems are typically suspended from a mounting surface, such as an exposed framing member, such as a joist, or an existing ceiling surface. The grid beams are typically suspended by a wire that is connected to the mounting surface and are arranged and attached to each other to form a rectangular patterned grid. Such suspended grid systems provide a means for lowering a ceiling surface to allow for the installation of utility fixtures, duct work, pipes, etc., above the ceiling surface. Access to such features is provided by the removal of one or more ceiling panels of the ceiling surface. The suspended grid system is also advantageous in that it allows easy replacement of a single panel if it becomes damaged, as opposed to replacing a complete section of a drywall or plaster ceiling. However, suspended ceiling grid systems have some disadvantages in certain applications. Many ceiling applications have space constraints, such as in a basement, where ceiling heights are typically less than standard construction ceiling heights. In these instances, suspended ceiling grid systems would suspend too low and minimize the height of the ceiling. Furthermore, many applications do not require an elaborate suspended grid system, which can be expensive due to the material requirements and labor requirements for installation. Therefore, a direct mount system for ceiling panels would minimize costs and maximize ceiling height.
Some prior art direct mount systems typically involve the direct application of panels or tile treatments to a ceiling mounting surface with adhesive, fasteners, screws, or other fastening means. Other prior art direct mount systems that utilize grid beams are not removable once a lower grid beam is assembled to an upper grid beam. These mounting arrangements make it difficult to replace sections of damaged ceiling panels. Furthermore, access to the space above the mounting surface from the inside of a room is often difficult due to the ceiling panels being positioned so close to the mounting surface. A panel must be lifted from the supporting ceiling grid and tilted for removal. The ceiling panel is obstructed from this movement because the mounting surface is too close to the back of the ceiling panel.
Therefore, it is an object of the present invention to provide a direct mount grid system that allows the installation of ceiling tiles close to the mounting surface thereby maximizing effective ceiling height of a room.
It is also an object of the present invention to provide a direct mount grid system having removable lower grid members to allow access to the space above the mounting surface after the ceiling has been installed.
It is also an object of the present invention to provide a direct mount grid system having removable lower grid members to allow replacement of damaged ceiling panels.
It is also an object of the present invention to provide a direct mount grid system that enables the use of standard lay-in ceiling panels.
These and other objects and advantages of the present invention will become apparent to those skilled in the art from the following description taken in conjunction with the drawings.